Writeacher, I urgently need to check this part regarding a scientific topic. I hope you can help me. Here is the first part.

1) In 1951 an American woman descended from African slaves freed named Henrietta Lacks, was admitted to Johns Hopkins Hospital in Baltimore. In those years, scientists has long tried unsuccessfully to grow human cells in the laboratory to carry out body searches of physiology and trials of new drugs that would never have been able to carry on living being.
2)Inevitably, the cells did not develop , because they still do not know exactly what nutrients they require, or became infected, or at least they proved too weak to grow.
3) This woman was diagnosed with cervical cancer from which the doctors carried off by some cells. Although the tumor was removed, the woman died the same year at the age of thirty.
4) But the cells of her cancer did not die with her. The doctors realized that these cells had some unique features never seen before.
5) First, these cells had an altered set of chromosomes; they possessed more than eighty chromosomes for the presence of an abnormal number of pairs of chromosomes 12, 6, 8, and 17.

1 answer

You verbs do not match the subjects, and often are in the wrong tense. See highlighted:
1) In 1951 an American woman descended from African slaves freed named Henrietta Lacks, was admitted to Johns Hopkins Hospital in Baltimore. In those years, scientists hadhas long tried unsuccessfully to grow human cells in the laboratory to carry out body searches of physiology ? and trials of new drugs that would never had have been able to carry on living being. what does her race, and heritage have to do with your essay?
2)Inevitably, the cells did not develop , because they still do not know exactly what nutrients they require, or became infected, or at least they proved too weak to grow.
3) This woman was diagnosed with cervical cancer from which the doctors carried off by? some cells. Although the tumor was removed, the woman died the same year at the age of thirty.
4) But the cells of her cancer did not die with her. The doctors realized that these cells had some unique features never seen before.
5) First, these cells had an altered set of chromosomes; they possessed more than eighty chromosomes for the presence of an abnormal number of pairs of chromosomes 12, 6, 8, and 17.

Your sentences are often long and fragmented. You try to use commas or semicolons to tie it up. Recheck those